54 research outputs found
Activation d'amides avec l'anhydride triflique en présence de pyridine : préparation de sels de pyridinium et application à la synthèse de dihydropyridines et de pipéridines
Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal
Les comités d'instruction publique sous la Révolution\ud Principaux rapports et projets de décrets: Lepeletier & Bouquier
Une reproduction en trois fascicules des grands rapports et projets de décrets qui ont jalonné le débat sur l'orientation de l'instruction publique à l'époque révolutionnaire. Ce Fascicule II présente les projets de Lepeletier-Robespierre et de Bouquier. Il est suivi d'analyses de textes assistées par ordinateur offrant un index alphabétique et fréquentiel des lexèmes-clés, des univers conceptuels, de tableaux des relations discursives, conceptuelles et idéologiques et un tableau comparatif général
Les comités d'instruction publique sous la Révolution\ud Principaux rapports et projets de décret : Condorcet & Romme
Une reproduction en trois fascicules des grands rapports et projets de décrets qui ont jalonné le débat sur l'orientation de l'instruction publique à l'époque révolutionnaire. Ce Fascicule I présente les projets de Condorcet et de Romme. Il est suivi d'analyses de textes assistées par ordinateur offrant un index alphabétique et fréquentiel des lexèmes-clés, des univers conceptuels, de tableaux des relations discursives, conceptuelles et idéologiques et un tableau comparatif général
Numerical evaluation of grouting scenarios for reducing water inflows in underground excavations – Goldcorp’s Éléonore mine study case
Water inflows through fracture networks are one of the many challenges that the Éléonore mine has to face. Although pregrouting
of pilot holes during mine development has been proven to efficiently reduce water inflows into mine excavations,
the actual design methods are empirical and can be optimized to increase grouting efficiency and decrease the associated
costs. Optimization of the amount of cement needed for pre-grouting is achieved by designing the grouting approach based
on the location of major faults around the excavations. Here, a base case finite-element numerical model and associated
sensitivity analyses are used to simulate groundwater inflows into a stope, based on the Éléonore mining site
characteristics. Simulations are conducted for testing various grout injection scenarios for various major fault locations
around the stope. Sensitivity analyses have shown that for a fault located above the stope, the inflow reduction is greater
when the zone between the fault and the stope is grouted instead of directly grouting the fault itself. Also, in the case of a
fault intersecting a stope, the results have demonstrated that the fault itself should be grouted as widely as possible, instead
of sealing only the immediate surroundings of the stope
Detailed Analysis of Nearby Bulgelike Dwarf Stars III. Alpha and Heavy-element abundances
The present sample of nearby bulgelike dwarf stars has kinematics and
metallicities characteristic of a probable inner disk or bulge origin. Ages
derived by using isochrones give 10-11 Gyr for these stars and metallicities
are in the range -0.80< [Fe/H]< +0.40. We calculate stellar parameters from
spectroscopic data, and chemical abundances of Mg, Si, Ca, Ti, La, Ba, Y, Zr
and Eu are derived by using spectrum synthesis.
We found that [alpha-elements/Fe] show different patterns depending on the
element. Si, Ca and Ti-to-iron ratios decline smoothly for increasing
metallicities, and follow essentially the disk pattern. O and Mg, products of
massive supernovae, and also the r-process element Eu, are overabundant
relative to disk stars, showing a steeper decline for metallicities [Fe/H] >
-0.3 dex. [s-elements/Fe] roughly track the solar values with no apparent trend
with metallicity for [Fe/H] < 0, showing subsolar values for the metal rich
stars. Both kinematical and chemical properties of the bulgelike stars indicate
a distinct identity of this population when compared to disk stars.Comment: 21 pages, 9 figures, to appear in Ap
Detailed Analysis of Nearby Bulgelike Dwarf Stars II. Lithium Abundances
Li abundances are derived for a sample of bulgelike stars with isochronal
ages of 10-11 Gyr. These stars have orbits with pericentric distances, Rp, as
small as 2-3 kpc and Zmax < 1 kpc. The sample comprises G and K dwarf stars in
the metallicity range -0.80<[Fe/H]< +0.40. Few data of Li abundances in old
turn-off stars (> 4.5 Gyr) within the present metallicity range are available.
M67 (4.7 Gyr) and NGC 188 (6 Gyr) are the oldest studied metal-rich open
clusters with late-type stars. Li abundances have also been studied for few
samples of old metal-rich field stars. In the present work a high dispersion in
Li abundances is found for bulgelike stars for all the metallicity range,
comparable with values in M67. The role of metallicity and age on a Li
depletion pattern is discussed. The possible connection between Li depletion
and oxygen abundance due to atmospheric opacity effects is investigated.Comment: 9 pages, 7 figure
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